In a display device comprising a pair of substrates opposed to each other, a structure involving the bonding one of the substrates on which signal lines, switching elements, pixel electrodes and the like are formed, and the other substrate on which a light-shielding layer, color filters and the like are formed, has been widely adopted. In such a display device, if a displacement in the bonding occurs between the substrates, a phenomenon of color mixing in which colors of adjacent pixels are visually mixed occurs, and the aperture ratio is lowered for the reason that the signal lines and the opposing light-shielding layer are displaced.
Recently, higher resolution and a higher aperture ratio have been required for display devices for smartphones or tablets. As the pixel size becomes small with a higher resolution, the aperture ratio becomes reduced since the proportion of signal lines and the light-shielding layer to the pixel area becomes higher. For example, an organic field light-emitting display device in which a first sub-pixel emitting light of a first color and a second sub-pixel emitting light of a second color are disposed in the same column line, and a third sub-pixel emitting light of a third color is disposed in a column line adjacent to the column line of the first sub-pixel and the second sub-pixel, is well known as an example of a technology for securing the aperture ratio while achieving high resolution.